Real Estate Assets - pro forma results (Details) $ / shares in Units, $ in Thousands	3 Months Ended								12 Months Ended
	Nov. 30, 2017 USD ($) ft² $ / shares	Aug. 31, 2017 USD ($) $ / shares	May 31, 2017 USD ($) $ / shares	Feb. 28, 2017 USD ($) $ / shares	Nov. 30, 2016 USD ($) $ / shares	Aug. 31, 2016 USD ($) $ / shares	May 31, 2016 USD ($) $ / shares	Feb. 29, 2016 USD ($) $ / shares	Nov. 30, 2017 USD ($) ft² $ / shares	Nov. 30, 2016 USD ($) $ / shares	Nov. 30, 2015 USD ($) $ / shares
Real Estate Assets
Rental revenue									$ 29,939	$ 26,487	$ 24,605
Revenue from property sales									13,945	4,364	3,483
Total revenue									43,884	30,851	28,088
Operating expenses of rental properties									8,866	8,250	8,415
Depreciation and amortization expense									10,064	8,797	7,668
Costs related to property sales									3,780	810	634
General and administrative expenses									8,552	7,367	7,057
Total expenses									31,262	25,224	23,774
Operating income	$ 843	$ 3,194	$ 8,671	$ (86)	$ 3,464	$ 1,089	$ 270	$ 804	12,622	5,627	4,314
Interest expense									(5,690)	(4,545)	(3,670)
Income before income tax provision									7,300	1,311	805
Income tax (provision) benefit									2,673	735	380
Net Income	$ (490)	$ 1,329	$ 4,727	$ (939)	$ 1,339	$ (49)	$ (379)	$ (335)	$ 4,627	$ 576	$ 425
Earnings per share:
Basic (in dollars per share) | $ / shares	$ (0.10)	$ 0.27	$ 0.95	$ (0.19)	$ 0.26	$ (0.01)	$ (0.07)	$ (0.07)	$ 0.92	$ 0.11	$ 0.08
Diluted (in dollars per share) | $ / shares	$ (0.10)	$ 0.26	$ 0.94	$ (0.19)	$ 0.26	$ (0.01)	$ (0.07)	$ (0.07)	$ 0.92	$ 0.11	$ 0.08
215 International
Real Estate Assets
Rental revenue									$ 722
Operating income									$ 112
Earnings per share:
Unleased space | ft²	73,000								73,000
215 International | As reported
Real Estate Assets
Rental revenue									$ 29,939
Revenue from property sales									13,945
Total revenue									43,884
Operating expenses of rental properties									8,866
Depreciation and amortization expense									10,064
Costs related to property sales									3,780
General and administrative expenses									8,552
Total expenses									31,262
Operating income									12,622
Interest expense									(5,690)
Other non-operating income									368
Income before income tax provision									7,300
Income tax (provision) benefit									(2,673)
Net Income									$ 4,627
Earnings per share:
Basic (in dollars per share) | $ / shares									$ 0.92
Diluted (in dollars per share) | $ / shares									$ 0.92
215 International | Adjustments
Real Estate Assets
Rental revenue									$ 370
Total revenue									370
Operating expenses of rental properties									39
Depreciation and amortization expense									470
Total expenses									509
Operating income									(139)
Income before income tax provision									(139)
Income tax (provision) benefit									51
Net Income									(88)
215 International | Pro forma
Real Estate Assets
Rental revenue									30,309
Revenue from property sales									13,945
Total revenue									44,254
Operating expenses of rental properties									8,905
Depreciation and amortization expense									10,534
Costs related to property sales									3,780
General and administrative expenses									8,552
Total expenses									31,771
Operating income									12,483
Interest expense									(5,690)
Other non-operating income									368
Income before income tax provision									7,161
Income tax (provision) benefit									(2,622)
Net Income									$ 4,539
Earnings per share:
Basic (in dollars per share) | $ / shares									$ 0.91
Diluted (in dollars per share) | $ / shares									$ 0.90